The invention solves two problems: the problem of stacking and aligning multiple battery cell holding frames for assembly and use in service, and the problem of flexibility to use different cooling methods.
The expanded use of high energy density batteries, such as Lithium-Polymer (LiPo) batteries, for a variety of relatively new applications, including various vehicular applications, such as automotive use in gas-electric and diesel-electric hybrid vehicles and plug-in electric vehicles, has placed increased demands on the battery technology, particularly the packaging technology for these batteries. Since a relatively large number of relatively large sized battery cells must be packaged together for use in battery modules for use in these applications, the development of low cost packaging technology that is particularly suited to high volume manufacturing and assembly of these battery modules is very important to the successful commercialization of this technology.
Previous packaging technology has been relatively complex, requiring numerous parts to assembly the battery cells into battery modules. These include several different plastic frames and supports used to capture cells, and then further assembly of a plurality of packaged cells containing these parts, including the use of numerous fasteners in conjunction with the assembly of plastic frames and associated frame components. They have also included molding plastic flanges or other features around the edges of, or over the entire surface of, each of the cells used in the battery module. Such molding procedures are generally undesirable due to the potential for damaging the battery cells, as well as the enhanced material and labor costs associated with molding, testing and inspecting such features.
Previously, the incorporation of alignment features into frames and associated components has been utilized to aid the assembly process, but this has been limited due to the sometimes cumbersome integration of these features, particularly in view of the number of parts that have been utilized to form and assemble battery frames and modules.
Previously, the need to incorporate cooling into the battery modules has also been difficult due to the large number of components involved in the assembly and the complexity added to the assembly thereby, as well as the need to maintain cooling in the assembly and minimize coolant leakage while also providing the needed thermal coupling in these complex assemblies. Because of the complexity associated with prior cooling schemes, alteration of the cooling system, including changes to the cooling apparatus and method employed has required significant redesign of the battery module. Thus, if the cooling load of the module was higher than anticipated, making changes to the cooling system has been difficult, generally requiring significant tooling changes, requalification of the cooling system and the like.
Thus, it is desirable to develop improved components for packaging battery modules having designs and materials that enable more simplified assembly and more versability for cooling the resultant modules while also providing the desired cost, structural, mechanical, thermal and other properties to the assembly.